The morphological differences in heat stressed rooster spermatozoa with shortened acrosomes. The intact acrosomes from fresh semen are indicated by black arrows, and the damaged acrosomes are indicated by white arrows (A) which mark the shortened or missing acrosomes (black arrow) (B). Each sperm (black rectangular box in A and B) was magnified to reveal the connected region between the sperm heads at (C) and (D). The linking area between head and acrosome cap is indicated by the hollow arrows. The scale bars in (A) and (B) represent 20 μM. The scale bars in (C) and (D) represent 10 μM.
